/*
 * $Id: PdfLine.java 4897 2011-06-07 15:09:25Z blowagie $
 *
 * This file is part of the iText (R) project.
 * Copyright (c) 1998-2011 1T3XT BVBA
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text.pdf;

import java.util.ArrayList;
import java.util.Iterator;

import com.itextpdf.text.Chunk;
import com.itextpdf.text.Element;
import com.itextpdf.text.Image;
import com.itextpdf.text.ListItem;

/**
 * <CODE>PdfLine</CODE> defines an array with <CODE>PdfChunk</CODE>-objects
 * that fit into 1 line.
 */

public class PdfLine {

    // membervariables

    /** The arraylist containing the chunks. */
    protected ArrayList<PdfChunk> line;

    /** The left indentation of the line. */
    protected float left;

    /** The width of the line. */
    protected float width;

    /** The alignment of the line. */
    protected int alignment;

    /** The height of the line. */
    protected float height;

    /** The listsymbol (if necessary). */
    protected Chunk listSymbol = null;

    /** The listsymbol (if necessary). */
    protected float symbolIndent;

    /** <CODE>true</CODE> if the chunk splitting was caused by a newline. */
    protected boolean newlineSplit = false;

    /** The original width. */
    protected float originalWidth;

    protected boolean isRTL = false;

    // constructors

    /**
     * Constructs a new <CODE>PdfLine</CODE>-object.
     *
     * @param   left            the limit of the line at the left
     * @param   right           the limit of the line at the right
     * @param   alignment       the alignment of the line
     * @param   height          the height of the line
     */

    PdfLine(float left, float right, int alignment, float height) {
        this.left = left;
        this.width = right - left;
        this.originalWidth = this.width;
        this.alignment = alignment;
        this.height = height;
        this.line = new ArrayList<PdfChunk>();
    }

    /**
     * Creates a PdfLine object.
     * @param left                              the left offset
     * @param originalWidth             the original width of the line
     * @param remainingWidth    bigger than 0 if the line isn't completely filled
     * @param alignment                 the alignment of the line
     * @param newlineSplit              was the line splitted (or does the paragraph end with this line)
     * @param line                              an array of PdfChunk objects
     * @param isRTL                             do you have to read the line from Right to Left?
     */
    PdfLine(float left, float originalWidth, float remainingWidth, int alignment, boolean newlineSplit, ArrayList<PdfChunk> line, boolean isRTL) {
        this.left = left;
        this.originalWidth = originalWidth;
        this.width = remainingWidth;
        this.alignment = alignment;
        this.line = line;
        this.newlineSplit = newlineSplit;
        this.isRTL = isRTL;
    }

    // methods

    /**
     * Adds a <CODE>PdfChunk</CODE> to the <CODE>PdfLine</CODE>.
     *
     * @param           chunk           the <CODE>PdfChunk</CODE> to add
     * @return          <CODE>null</CODE> if the chunk could be added completely; if not
     *                          a <CODE>PdfChunk</CODE> containing the part of the chunk that could
     *                          not be added is returned
     */

    PdfChunk add(PdfChunk chunk) {
        // nothing happens if the chunk is null.
        if (chunk == null || chunk.toString().equals("")) {
                return null;
        }

        // we split the chunk to be added
        PdfChunk overflow = chunk.split(width);
        newlineSplit = chunk.isNewlineSplit() || overflow == null;
        if (chunk.isTab()) {
                Object[] tab = (Object[])chunk.getAttribute(Chunk.TAB);
                float tabPosition = ((Float)tab[1]).floatValue();
                boolean newline = ((Boolean)tab[2]).booleanValue();
                if (newline && tabPosition < originalWidth - width) {
                    return chunk;
                }
                width = originalWidth - tabPosition;
                chunk.adjustLeft(left);
            addToLine(chunk);
        }
        // if the length of the chunk > 0 we add it to the line
        else if (chunk.length() > 0 || chunk.isImage()) {
            if (overflow != null)
                chunk.trimLastSpace();
            width -= chunk.width();
            addToLine(chunk);
        }
        // if the length == 0 and there were no other chunks added to the line yet,
        // we risk to end up in an endless loop trying endlessly to add the same chunk
        else if (line.size() < 1) {
            chunk = overflow;
            overflow = chunk.truncate(width);
            width -= chunk.width();
            if (chunk.length() > 0) {
                addToLine(chunk);
                return overflow;
            }
            // if the chunk couldn't even be truncated, we add everything, so be it
            else {
                if (overflow != null)
                    addToLine(overflow);
                return null;
            }
        }
        else {
            width += (line.get(line.size() - 1)).trimLastSpace();
        }
        return overflow;
    }

    private void addToLine(PdfChunk chunk) {
        if (chunk.changeLeading && chunk.isImage()) {
                Image img = chunk.getImage();
                float f = img.getScaledHeight() + chunk.getImageOffsetY()
                        + img.getBorderWidthTop() + img.getSpacingBefore();
                if (f > height) height = f;
        }
        line.add(chunk);
    }

    // methods to retrieve information

    /**
     * Returns the number of chunks in the line.
     *
     * @return  a value
     */

    public int size() {
        return line.size();
    }

    /**
     * Returns an iterator of <CODE>PdfChunk</CODE>s.
     *
     * @return  an <CODE>Iterator</CODE>
     */

    public Iterator<PdfChunk> iterator() {
        return line.iterator();
    }

    /**
     * Returns the height of the line.
     *
     * @return  a value
     */

    float height() {
        return height;
    }

    /**
     * Returns the left indentation of the line taking the alignment of the line into account.
     *
     * @return  a value
     */

    float indentLeft() {
        if (isRTL) {
            switch (alignment) {
                case Element.ALIGN_LEFT:
                    return left + width;
                case Element.ALIGN_CENTER:
                    return left + width / 2f;
                default:
                    return left;
            }
        }
        else if (this.getSeparatorCount() <= 0) {
            switch (alignment) {
                case Element.ALIGN_RIGHT:
                    return left + width;
                case Element.ALIGN_CENTER:
                    return left + width / 2f;
            }
        }
        return left;
    }

    /**
     * Checks if this line has to be justified.
     *
     * @return  <CODE>true</CODE> if the alignment equals <VAR>ALIGN_JUSTIFIED</VAR> and there is some width left.
     */

    public boolean hasToBeJustified() {
        return (alignment == Element.ALIGN_JUSTIFIED || alignment == Element.ALIGN_JUSTIFIED_ALL) && width != 0;
    }

    /**
     * Resets the alignment of this line.
     * <P>
     * The alignment of the last line of for instance a <CODE>Paragraph</CODE>
     * that has to be justified, has to be reset to <VAR>ALIGN_LEFT</VAR>.
     */

    public void resetAlignment() {
        if (alignment == Element.ALIGN_JUSTIFIED) {
            alignment = Element.ALIGN_LEFT;
        }
    }

    /** Adds extra indentation to the left (for Paragraph.setFirstLineIndent). */
    void setExtraIndent(float extra) {
        left += extra;
        width -= extra;
    }

    /**
     * Returns the width that is left, after a maximum of characters is added to the line.
     *
     * @return  a value
     */

    float widthLeft() {
        return width;
    }

    /**
     * Returns the number of space-characters in this line.
     *
     * @return  a value
     */

    int numberOfSpaces() {
        String string = toString();
        int length = string.length();
        int numberOfSpaces = 0;
        for (int i = 0; i < length; i++) {
            if (string.charAt(i) == ' ') {
                numberOfSpaces++;
            }
        }
        return numberOfSpaces;
    }

    /**
     * Sets the listsymbol of this line.
     * <P>
     * This is only necessary for the first line of a <CODE>ListItem</CODE>.
     *
     * @param listItem the list symbol
     */

    public void setListItem(ListItem listItem) {
        this.listSymbol = listItem.getListSymbol();
        this.symbolIndent = listItem.getIndentationLeft();
    }

    /**
     * Returns the listsymbol of this line.
     *
     * @return  a <CODE>PdfChunk</CODE> if the line has a listsymbol; <CODE>null</CODE> otherwise
     */

    public Chunk listSymbol() {
        return listSymbol;
    }

    /**
     * Return the indentation needed to show the listsymbol.
     *
     * @return  a value
     */

    public float listIndent() {
        return symbolIndent;
    }

    /**
     * Get the string representation of what is in this line.
     *
     * @return  a <CODE>String</CODE>
     */

    @Override
    public String toString() {
        StringBuffer tmp = new StringBuffer();
        for (PdfChunk pdfChunk : line) {
            tmp.append((pdfChunk).toString());
        }
        return tmp.toString();
    }

    /**
     * Returns the length of a line in UTF32 characters
     * @return  the length in UTF32 characters
     * @since   2.1.2; Get changed into get in 5.0.2
     */
    public int getLineLengthUtf32() {
        int total = 0;
        for (Object element : line) {
            total += ((PdfChunk)element).lengthUtf32();
        }
        return total;
    }

    /**
     * Checks if a newline caused the line split.
     * @return <CODE>true</CODE> if a newline caused the line split
     */
    public boolean isNewlineSplit() {
        return newlineSplit && alignment != Element.ALIGN_JUSTIFIED_ALL;
    }

    /**
     * Gets the index of the last <CODE>PdfChunk</CODE> with metric attributes
     * @return the last <CODE>PdfChunk</CODE> with metric attributes
     */
    public int getLastStrokeChunk() {
        int lastIdx = line.size() - 1;
        for (; lastIdx >= 0; --lastIdx) {
            PdfChunk chunk = line.get(lastIdx);
            if (chunk.isStroked())
                break;
        }
        return lastIdx;
    }

    /**
     * Gets a <CODE>PdfChunk</CODE> by index.
     * @param idx the index
     * @return the <CODE>PdfChunk</CODE> or null if beyond the array
     */
    public PdfChunk getChunk(int idx) {
        if (idx < 0 || idx >= line.size())
            return null;
        return line.get(idx);
    }

    /**
     * Gets the original width of the line.
     * @return the original width of the line
     */
    public float getOriginalWidth() {
        return originalWidth;
    }

    /*
     * Gets the maximum size of all the fonts used in this line
     * including images.
     * @return maximum size of all the fonts used in this line
     float getMaxSizeSimple() {
        float maxSize = 0;
        PdfChunk chunk;
        for (int k = 0; k < line.size(); ++k) {
            chunk = (PdfChunk)line.get(k);
            if (!chunk.isImage()) {
                maxSize = Math.max(chunk.font().size(), maxSize);
            }
            else {
                maxSize = Math.max(chunk.getImage().getScaledHeight() + chunk.getImageOffsetY() , maxSize);
            }
        }
        return maxSize;
    }*/

    /**
     * Gets the difference between the "normal" leading and the maximum
     * size (for instance when there are images in the chunk and the leading
     * has to be taken into account).
     * @return  an extra leading for images
     * @since   2.1.5
     */
    float[] getMaxSize() {
        float normal_leading = 0;
        float image_leading = -10000;
        PdfChunk chunk;
        for (int k = 0; k < line.size(); ++k) {
            chunk = line.get(k);
            if (!chunk.isImage()) {
                normal_leading = Math.max(chunk.font().size(), normal_leading);
            }
            else {
                Image img = chunk.getImage();
                if (chunk.changeLeading()) {
                        float height = img.getScaledHeight() + chunk.getImageOffsetY() + img.getSpacingBefore();
                        image_leading = Math.max(height, image_leading);
                }
            }
        }
        return new float[]{normal_leading, image_leading};
    }

    boolean isRTL() {
        return isRTL;
    }

    /**
     * Gets the number of separators in the line.
     * Returns -1 if there's a tab in the line.
     * @return  the number of separators in the line
     * @since   2.1.2
     */
    int getSeparatorCount() {
        int s = 0;
        PdfChunk ck;
        for (Object element : line) {
                ck = (PdfChunk)element;
                if (ck.isTab()) {
                        return -1;
                }
                if (ck.isHorizontalSeparator()) {
                        s++;
                }
        }
        return s;
    }

    /**
     * Gets a width corrected with a charSpacing and wordSpacing.
     * @param charSpacing
     * @param wordSpacing
     * @return a corrected width
     */
    public float getWidthCorrected(float charSpacing, float wordSpacing) {
        float total = 0;
        for (int k = 0; k < line.size(); ++k) {
            PdfChunk ck = line.get(k);
            total += ck.getWidthCorrected(charSpacing, wordSpacing);
        }
        return total;
    }

/**
 * Gets the maximum size of the ascender for all the fonts used
 * in this line.
 * @return maximum size of all the ascenders used in this line
 */
   public float getAscender() {
       float ascender = 0;
       for (int k = 0; k < line.size(); ++k) {
           PdfChunk ck = line.get(k);
           if (ck.isImage())
               ascender = Math.max(ascender, ck.getImage().getScaledHeight() + ck.getImageOffsetY());
           else {
               PdfFont font = ck.font();
               ascender = Math.max(ascender, font.getFont().getFontDescriptor(BaseFont.ASCENT, font.size()));
           }
       }
       return ascender;
   }

/**
 * Gets the biggest descender for all the fonts used
 * in this line.  Note that this is a negative number.
 * @return maximum size of all the descenders used in this line
 */
    public float getDescender() {
        float descender = 0;
        for (int k = 0; k < line.size(); ++k) {
            PdfChunk ck = line.get(k);
            if (ck.isImage())
                descender = Math.min(descender, ck.getImageOffsetY());
            else {
                PdfFont font = ck.font();
                descender = Math.min(descender, font.getFont().getFontDescriptor(BaseFont.DESCENT, font.size()));
            }
        }
        return descender;
    }
}